// 交叉类型：将多个类型合并成的类型就是交叉类型
type objtype1 = { username: string, age: number }
type objtype2 = { phone: string, age: number }

let jiaochatype: objtype1 & objtype2 = {
  username: 'burt',
  age: 18,
  phone: '1517134565'
}